#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>

#include <stdio.h>
#include <math.h>

int main()
{
    int m = 0;
    scanf("%d", &m);

    int x = pow(m, 2);
    int bigan = x - (m - 1);

    for (int i = 0; i < m; i++)
    {
        i == 0 ? printf("%d", bigan) : printf("+%d", bigan);
        bigan += 2;
    }
    return 0;
}

#include <stdio.h>

int main()
{
    int n = 0;
    scanf("%d", &n);
    int x = 3 * n - 1;
    printf("%d", n * 2 + n * (n - 1) * 3 / 2);
    return 0;
}

#include <stdio.h>

int main()
{
	int a = 3;
	printf("%d", (a += a -= a * a));
	return 0;
}

#include <stdio.h>

int main()
{
    int n = 0;
    double sum = 0;
    int count = 0;
    int ngcount = 0;
    scanf("%d", &n);

    int arr[n];
    for (int i = 0; i < n; i++)
    {
        scanf("%d", &arr[i]);
        if (arr[i] > 0)
        {
            sum += arr[i];
            count++;
        }
        else if (arr[i] < 0)
        {
            ngcount++;
        }
    }
    printf("%d ", ngcount);
    if (count == 0)
    {
        printf("0.0");
    }
    else
    {
        printf("%.1lf", sum / count * 1.0);
    }

    return 0;
}